A concept should not attempt to serve two distinct purposes; this leads to conflicts and confusion.

Entities in the same semantic neighborhood but without a typed relation to this one — candidates for new edges or unrecognized duplicates.

• Two concepts should not have the same purpose; additional concepts for the same purpose create needless complexity.claim0.866
  No redundancy criterion.
• A concept should have an articulated purpose; without it, there is no reason from the user’s point of view.claim0.832
  Motivation criterion justification.
• The operational principle of a concept should mention only that concept and its directly or indirectly depended concepts.claim0.803
  A rule relating operational principle to dependence graph.
• The four concept criteria (motivation, no redundancy, no overloading, uniformity) are neither necessary nor sufficient but can explain design flaws.claim0.800
  Acknowledging the heuristic nature of the criteria.
• Concepts are not just subjective mental constructs, but are objective features of a system's design: increments of functionality that were consciously introduced by a designer to serve particular purposes.concept0.785
  Central definition from the abstract.
• Piggybacking a new purpose onto an existing concept (overloading) causes conflicts and design flaws.claim0.784
  Illustrated with OS X print subsystem example.
• For some purposes, it will be convenient to settle for specifications in terms of fulfilling internal commitments, and sometimes the public character of promises will have to be taken into account in the specifications.claim0.779
  Trade-off between internal and public obligations.
• Contrast, instead of separating things, brings them together when used to help centers become alive; contrast that fails to create deeper feeling is merely accidental or eye-catchingclaim0.779
  Claim distinguishing good contrast (Shaker schoolroom, which unifies) from bad contrast (glaring lobby staircase, which separates)